In the related art, in a power conversion apparatus that converts direct-current power supplied from a direct-current power supply into alternating-current power, a smoothing capacitor that suppresses a voltage variation of the direct-current power from being generated due to switching operation at the time of converting power and smoothes the direct-current power is provided. Technology for discharging charges accumulated in the smoothing capacitor when high voltage DC side is separated in the power conversion apparatus has been known.
For example, in PTL 1, technology for allowing a motor control mechanism in a microcomputer to switch a switching element of an inverter circuit, flowing a current to an external load, and discharging charges accumulated in a smoothing capacitor, when a main contactor is turned off, has been disclosed.
In addition, in PTL 2, technology for connecting an external discharge resistor and a switching element between both ends of a smoothing capacitor and establishing electrical continuity with the switching element and starting discharge, according to a discharge signal output only when the discharge is necessary, has been disclosed.